We need to go back to the 1960s/1970s, where Tektronix oscilloscopes and other such equipment came with user manuals that had detailed explanations of how the electronics worked.
As an example, check out the user manual (not the repair manual, though that's available on this site too) for the popular Tektronix 465, and scroll down to the "Circuit Description" section:
https://w140.com/tekwiki/wiki/Main_Page https://bama.edebris.com/manuals/tek
As an example, check out the user manual (not the repair manual, though that's available on this site too) for the popular Tektronix 465, and scroll down to the "Circuit Description" section:
https://bama.edebris.com/download/tek/465/465_v6.pdf